It is known in the art to separate the tail or flash from the bottom of a container that has been formed by a blow molding operation by exerting a tensile force between the container and the flash to cause a separation thereof. Apparatus for carrying out such an operation is disclosed, for example, in U.S. Pat. No. 3,677,454, patented July 18, 1972 in the name of Boyer. As disclosed in this patent, the flash is grasped between two moving chains and the tensile force necessary for severing the flash from the container is provided by moving the chains to which the flash is attached so that the container is forced to travel up an inclined plane away from the chains while the flash continues to travel in a linear course with the chains.
It is also known to provide flash trimming apparatus wherein the containers are grasped by a pair of side gripper belts and are transported on a conveyor, and the flash is then torn away by a pair of endless chains that grasp the flash as the containers are transported. The chains accomplish this result by laterally twisting the flash from the path of travel of the containers. Apparatus of this type is disclosed in U.S. Pat. No. 3,098,593, patented July 23, 1963 in the name of Heider.
Other known forms of apparatus for trimming flash from blown containers are disclosed in the following U.S. Pat. Nos.:
3,464,084--Sept. 2, 1969--Thompson; PA1 3,172,152--Mar. 9, 1965--Uhlig; PA1 3,040,376--June 26, 1962--Elphee.
There remains a need for improvements over the prior art in the trimming of flash from containers. In particular, a need exists for improved apparatus which will allow the containers to be advanced continuously by a conveyor system in upright positions to the trimming station, at which the containers are trimmed more expeditiously and returned to the conveyor system in the same upright positions without slowing down the flow of containers and without upsetting any of them so as to interfere with either the trimming or the subsequent operations that are to be performed in connection with the containers.